Improvement in semi-rotary valves



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VJOSEIHUS F'. HOLLOWYfOF V'CLEV'ELAND,v OHIO.`

Letters Patent No. 119,041., dated December 13, 1870.

IMPROVEMENT IN SEMI-ROTARY VALVES.

The Schedule referred to in these Letters Patent and making part of the same.

I,'-JOSEPHUS F. HOLLOWAY, of Cleveland, in the county of Cuyahoga and State of Ohio, have invented a new and improved mode of constructing Slide-Valves for Steam or other Engines, of which the yfollowing is a specification. Y

VNature and Object of the Invention.

tion, and consequently the wear upon the face of the valve, and upon the face of the valve-seat.

My invention is intended to apply to that class of steam or othei` engines in which the valve-seat or chamber is bored out cylindrical, and the main or slidevalve is xed upon a round spindle or valve-stem, which is concentric with the valve-chamber, and the face of the valve is turnedtrnly to t upon the valve-seat, and semi-rotates within and upon the valve-seat.

Description of the Accompanying Drawing.

Figure l is a side elevation of the steam-cylinder, showing an end view ofthe valve-chamber and of the valve, the whole being .a cross-section through the center of the steam-cylinder.

4Figure 2 is an end elevation of the steam-cylinder,

showing a longitudinal cross-section through the center of the valve-chamber, and the valve-spindle and valve. Y

Similar letters refer to the same parts in both figures.

General Description.

A is the steam-cylinder. B is the main or slide-valve. O is the pistonhead and packing. D is the piston-rod. A

E is the valve-spindle or stem. F is a connecting screw-bolt or rod. G is a'loos'e sleeve on the 'valve-stem; His a thin circular metallic disk. I is a metal ring to fasten the disk H. J is e broad-faced nut closed vat top. K is a broad-faced nut. L is the steam-opening into the chamber'. The steam-cylinder A,'as shown in the` drawing, has a circular steam-chest cast on it, and the steamchest'is bored out truly,-and at right angles with the bore of vthe cylinder. g The steam-chest may becast separately and bolted ont the steam-cylinder if it is more convenient to do so.

- Within the steam-chest is the main or slide-telve B. This valve is keyed, or otherwise fastened to the` valve-spindle 1t, and is made to semi-rotate within the steam-chest by means of a crank on the end of the valve-spindle, this crank being actuated by an ec centric in'the usual manner; thusA admitting and discharging the steam through the ports into the cylinder iu thesame manner as is done bythe common slide-valve.

For the purpose of relieving the valve of a portion of the pressure which is upon -it when ,steam is admitted into the steam-chest, I place ou the valvespindle E, midway from each end, a loose sleeve, G, which is bored out alittle larger than the spindle, so that the spindle may turn freely within it.

In the top of this sleeve G is attached abolt, F, and on the 'top of the steam-chest, or opposite the ex-A haust port of the steamcylinder, is an opening, which I cover with a thin flexible plate 5f metal, marked H in the drawing. This plate is held in its place and made steam-tight hy the ring I, which is bolted to the steam-chest.

rllhis tlexible plate H has in its center a hole, through which the bolt 11 projects, and it is prevented from being blown out by the pressure of vsteam within the steam-chest by the broad-faced nut or a broad washer and nut J, which is screwed onto the bolt F, and rests on the outer face of the plate. v

-K is also a nut, screwed on the bolt F, within the steam-chest, and on thc under side of the plate H, having between it and the plate a thin gasket of rnbber cloth, which prevents the escape of steam through the hole in the plate H. v

It will be obvious to any one that the amount ot' pressure exerted upon the underside of the exible plate H, will be governed by the amount ot' its outer surface exposed tothe atmosphere, or, in other words, by the area of the plate not covered by the ring I; thus the amount of pressure it is desirable to take olf the main valves can be regulated by the size of the inner diameter of the ring I.

Precisely how much should be thus counterbalanced or taken oi the valve B is, to some extent, a matter ofexperiment, but in practice I make the area of tlie: plate wit-hin the ring to eqnalthe area of the exhaustchamber under the main valve, thus reliev ing the face of the valve of a large portion of the pressure, and consequently the friction upon it.

I do not confine myself to the use of a single sleeve, bolt, and plate, for one valve, but-use two or more sleeves, bolts, plates, and rings, when the valve is large enough to warrant it. Neither do I confine myself to the peculiar method, as'shown, by which to connect the sleeve G and the plate H.

Claims.

" -I claim as my inventionl. The combination of the boit or.oonneotingbztr sleeve G, substantially as described, and for the pnl'- F, in connection with the sleeve G, and the nuts J poses set forth.

and K, on either side of the flexible plate H, sub- JOSEPHUSF. HOLLO\VAY. stantially as and for the purpose hereinbefore set v forth. Y WVitnesses 2. The combination of the flexible plate H, in con- Itoml CARTWRIGHT,

nection with the connecting-bar F and the loose WILLIAM \V. CASTLE. 

